Perhaps you should try some spelling variations:
"international africa's economic theories" » "international african economic theories", "international prices economic theories", "international airways economic theories", "international africa economic theories", "international china's economic theories", "international africa's economic theory", "international africa's economics series"
"international policy economic services" » "international poverty economic services", "international prices economic services", "national policy economic services", "international policy economics series", "international policy ecological services", "international policy economic studies"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("international africa's economic theories") or ("international policy economic services"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international africa's economic theories") OR ("international policy economic services")).
• Removing quotes may allow a broader search: (( international africa's economic theories ) or ( international policy economic services )).
• Adding a wildcard symbol may retrieve word variants: (("international africa's economic theories") or ("international policy economic services"))*.